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Comment Re:That's Heavy (Score 2) 201

There are plenty of incremental steps that could be pursued to drive R&D and expand the industry, such as near-Earth space tourism (as you suggest), asteroid mining, space-based solar, and small-scale research and exploration colonies that aren't intended to be self-sufficient. All of these things would benefit greatly from a huge reusable rocket like the ITS, without the high probability of catastrophic, deadly, horrendously expensive failure that accompanies a premature large-scale colonization effort.

I tend to agree... if we have to find the "next Earth", then Mars is certainly the best candidate in the solar system, but I don't think there's any real requirement or capability for that kind of thing at the moment. Instead, just opening up a new economic frontier in space will probably be the real key to what Musk is after - moving humanity into the next phase of civilization. It might be that he even recognizes that (and the fact that this has been renamed the Interplanetary Transport System rather than the Mars Colonial Transporter suggests that he does) but is maintaining the vision of Mars because it provides the focus needed to hone the development effort. If he builds transportation infrastructure sufficient for a Mars colony, that same capability effectively unlocks the whole solar system to large-scale manned operations. Yet, it is still useful to focus on one specific mission to help sell the idea and cut out the cruft and feature creep along the way... and that way, nobody can call his system a "rocket to nowhere", a moniker that has plagued the entire SLS effort.

Comment Re:That's Heavy (Score 2) 201

You have a very narrow view of aerospace if you think its most important product is launch vehicles, or that the only design goal worth mentioning is raw power.

Not at all, I'm well aware of the advancements in satellite technology because I work directly in that field (and, FWIW, 90's era processors are still considered state-of-the-art in some contexts) - but my original contention was this: "[Apollo] was arguably the pinnacle of manned space capability and we still haven't matched it with modern systems." It's irrefutably true - the only manned system that's even operational as of today (Soyuz) literally predates even the Apollo program.

That's a false premise: costs did come down. Even the Delta IV heavy - widely regarded as badly overpriced compared to its contemporaries - is about 30% cheaper to launch on a per-ton basis than the Saturn V ever was.

Sure, but Delta IV isn't man-rated, so it better be cheaper than Saturn V. And, even if it was, a 30% decrease really is a pittance, especially considering that the capability is much lower. What's more, the Delta IV is a commercial operation, while Saturn V was a no-expense-spared national prestige program - you would think it ought to be dramatically cheaper by comparison. Of course, it isn't fair to compare to computers, because Moore's Law growth is unprecedented in any industry and we've never seen that kind of growth anywhere else, but if we looked to airliners which are more comparable, this would be like having intercontinental flights in the 70's, and today we can only fly cross-country, but still have to pay 70% of the original price. Pretty tepid "advancement".

As for SpaceX... what they've done is quite amazing.

Their internal technical capabilities aren't as far ahead of their competitors as the external results make it appear though: they're "standing on the shoulders of giants".

I totally agree. They haven't innovated technically as much as they've innovated with the economics of spaceflight. The development costs for their vehicles are peanuts. This might be because they've taken a page out of agile software development - start with a poorly optimized, bare minimum launcher (the original Merlin engine and Falcon 9 had pretty miserable performance compared to today) and iterate to get successively better. As well, in a sense they've done something "Apple-esque", in terms of taking existing hardware that isn't groundbreaking, but integrating it in a much more effective way than prior companies have done. And, they've had a very different motivation - in the short term for ULA or any of the entrenched launch providers, lowering costs means that you lose money, because the launch market is small enough and slow moving enough that it will take a while for demand to ramp up and for increased volume to make up for your lower per-launch cost. Which is why the launch industry has been more or less stagnant for 50 years. You need someone commercial, and who can look past the next 5-10 years of profits - we haven't gotten it until Musk and Bezos.

The problem with that, is that currently the technology does not exist to build a self-sustaining colony anywhere but on Earth, even with cheap space launch.

I think this is the classic "if you build it, they will come" scenario. You couldn't start a software company in 1970, and you can't start an orbital tourism company today. The hope is, cheap launch capability will bring these companies out of the woodwork, and it really ought to be a separate venture from launch, because ideally colonization hardware should be vehicle-agnostic. Personally, I think in the short term, orbital tourist stations could be a lot more lucrative than Mars - how many people would spend $20k for a 2-week space vacation in LEO, vs spending $200k for a multi-year (or one way) voyage to Mars? Either way, those prices are decades away, but I expect the order of magnitude difference between them will remain indefinitely, and I bet you there will always be more than 10x as many LEO travelers as Mars travelers.

Comment Re:That's Heavy (Score 1) 201

Materials have gotten lighter and stronger, computers have gotten immeasurably better in every respect, manufacturing capabilities have improved - so we've made advancements in individual areas. But as an integrated system, it's a simple fact that the Apollo program produced the most powerful launch vehicle ever created.

The modern aerospace industry has innovated in some areas, but in terms of launch vehicles we're still doing the same basic things as in the Apollo days - expendable rockets, throwing away hundreds of millions of dollars on every launch... If we're so much more advanced, why haven't costs come down? Why haven't capabilities increased? The state of the art didn't increase meaningfully (in production systems) until SpaceX and now Blue Origin came along.

Comment Re:Haha no. (Score 1) 113

It's almost impossible to predict the "killer app" for a technology before it becomes available. The PC was around as a hobbiest contraption for quite a few years before it became a serious business tool, the internet was around for a while before Google and Facebook learned that targeted advertising and data collection were the real cash cows (and became some of the largest corporations in the world)... nobody predicted in the early days of the internet that collecting user data would be so lucrative. They never imagined that something like a social network would become so significant or that a company like Facebook could become such a prominent corporation.

So, on some level, it's going to be a matter of lowering costs and building the infrastructure, and then waiting to see what crops up. Space tourism gets a lot of press, and it might be overstated, but I can say for a fact that if you get the cost low enough a huge market will emerge. At $100k/ticket, would you pay for a flight to orbit? Nah. At $10k? Maybe. At $1k? Hell yes.

So Musk is pulling out all the stops to drive that price/lb into the dirt and planning on the market to respond. But he's dumping his own cash into the business to do it, and in the short term, if you have 20 launches in the global market, and all of a sudden SpaceX does 10 of them for half the standard price, the net effect is that now there's 25% less global spending on the launch market. So the question is how fast the market will respond to the decreases in price, and if the increase in volume will be enough to offset the decrease in per-launch spending. Traditionally, that's how markets have worked, but if it ends up being a lot more lethargic, or less elastic, than Musk is projecting, he could run out of cash (or die of old age) before he succeeds in making space access routine and affordable.

Comment Re:nice video, but the launch seems backwards (Score 5, Informative) 201

Consider the fact that this is a promo video, just meant to demonstrate the architecture in layman's terms. In reality, sounds like during the 2-year wait between launch windows, these things will by flying continually, bringing up cargo and fuel to prep the transports. Crews will be sent up last, right before departure. Many ships are meant to make the trip simultaneously.

Comment Re:The Refueling Tanker makes no sense (Score 1) 201

All you really need for re-use is extra fuel - the legs and fins don't add a lot of mass. In addition, you still get a ton of atmospheric deceleration to help you out on the way down, and the rocket is far lighter on the return trip so you don't need to burn as much fuel for the same acceleration as you do when you are taking off with a full load.

So, all told, it's about 7% of fuel set aside to enable reuse. Pretty small price to pay to save your entire rocket. It also lessens your payload - but all the projections and designs that have been shown assume reuse, so the ITS can be launched with that existing payload penalty.

Comment Re:"the free blah blah blah of space" (Score 1) 209

...we're likely to need robots on the Moon to extract rocket fuel from the polar regolith

There are any number of places to get rocket fuel in the solar system: water from comets, or the polar regions of the Moon or Mars, or just go straight to Mars and synthesize CO and O2 straight from the Martian atmosphere using nuclear reactors. Which place ends up being most attractive is going to be highly dependent on the capabilities and needs of the launch industry - if everything converges around methane (which it's looking to do, at least based on SpaceX and Blue Origin's exploration-class vehicles) then that works nicely with Mars, assuming you bring some hydrogen with you at first and then move on towards getting it from the poles or the rumored subsurface supplies. The moon is one good option, but it's not by any means a given that we'll have to go there first.

In short, you need that supply chain. Or you need to hump every kilo of that material from Earth to your first industrial site and then build your supply chain.

I agree with this. Once we get serious about space, the absolute top priority will be building up that supply infrastructure - and if we can make LEO cheap and routine, I think that will happen pretty fast.

Comment At least one organization is doing some of this... (Score 1) 537

Living Goods is a pretty cool charity that I just started supporting recently. They focus on educating and equipping community health workers that sell basic health and sanitation products in impoverished regions. It's pretty awesome, actually - the health workers fund themselves by selling these products, it grows the local economy by creating jobs, it spreads information and supplies to stop the spread of avoidable disease.

The tech comes in because they've developed an app that assists in diagnosis of common, treatable ailments, and provides info and scheduling about checkups on prenatal care, all of which can have a big impact on health. Also, they've actually run some randomized trials that have shown something like a 30% reduction in infant mortality in communities that are served by this charity, which also qualifies as a "nerdy" IMO because many charities are driven by ideology and dogma and aren't interested in gathering quantifiable evidence that their services actually make a difference.

If you want to check them out: https://livinggoods.org/what-w...

I'm not affiliated with them except that I recently became a donor. I thought their approach was truly unique in the world of charitable giving.

Comment Re:"the free blah blah blah of space" (Score 1) 209

But I would think that the process of developing then necessary technologies in good time to deploy them if needed, is a fairly good investment.

I agree, but I think that can be a separate effort - making infrastructure projects more difficult/expensive than they have to be just to learn some things about asteroid relocation is going to be a worse solution IMO than making them distinct efforts - efficient asteroid mining, and efficient asteroid redirection.

Lets look at some numbers. If you can fit a single astronaut into a sphere 1.5m in diameter without them going insane (note the "if" - as a caver (EN_US: spelunker], I'd find a week in a 1.5m chamber wearing.

What I envision is something like an emergency bunker that is just large enough to fit the whole crew, and surrounded by some combination of fuel tanks, water supply, waste, and other massive materials that you'll be bringing with you anyway. This can provide pretty adequate shielding without much extra mass, but as you point out, it's going to be cramped. For that reason I would classify this as a short-term solution that is tolerable for exploration missions (and much better than the Apollo crews had) but not for sustained habitation. That's why I contend that we need orbiting manned facilities to be in LEO until we can afford the mass to shield large portions of a station. Which won't really happen IMO until we are mining asteroids.

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